The number is for the nearest phone box in the shot. These payphones do see quite heavy use from locals and tourists.

Bowes & Bowes was a bookseller and publishing company located at 1 Trinity Street, a corner position at the junction with St Mary's Street. It has a claim to be the oldest bookshop in the United Kingdom, with books having been sold on the site since 1581.[5] The Bowes & Bowes shop closed in 1986 and it was taken over by Sherratt & Hughes, which itself closed in 1992. Since then, the site has become the Cambridge University Press bookshop.